1 files changed, 48 insertions, 0 deletions
diff --git a/spec/ruby/library/zlib/gzipreader/rewind_spec.rb b/spec/ruby/library/zlib/gzipreader/rewind_spec.rb
new file mode 100644
index 0000000000..70bee3372d
--- /dev/null
+++ b/spec/ruby/library/zlib/gzipreader/rewind_spec.rb
@@ -0,0 +1,48 @@
+require File.expand_path('../../../../spec_helper', __FILE__)
+require 'stringio'
+require 'zlib'
+
+describe "GzipReader#rewind" do
+
+  before :each do
+    @data = '12345abcde'
+    @zip = [31, 139, 8, 0, 44, 220, 209, 71, 0, 3, 51, 52, 50, 54, 49, 77,
+            76, 74, 78, 73, 5, 0, 157, 5, 0, 36, 10, 0, 0, 0].pack('C*')
+    @io = StringIO.new @zip
+    ScratchPad.clear
+  end
+
+  it "resets the position of the stream pointer" do
+    gz = Zlib::GzipReader.new @io
+    gz.read
+    gz.pos.should == @data.length
+
+    gz.rewind
+    gz.pos.should == 0
+    gz.lineno.should == 0
+  end
+
+  it "resets the position of the stream pointer to data previously read" do
+    gz = Zlib::GzipReader.new @io
+    first_read = gz.read
+    gz.rewind
+    first_read.should == gz.read
+  end
+
+  it "invokes seek method on the associated IO object" do
+    # first, prepare the mock object:
+    (obj = mock("io")).should_receive(:get_io).any_number_of_times.and_return(@io)
+    def obj.read(args); get_io.read(args); end
+    def obj.seek(pos, whence = 0)
+      ScratchPad.record :seek
+      get_io.seek(pos, whence)
+    end
+
+    gz = Zlib::GzipReader.new(obj)
+    gz.rewind()
+
+    ScratchPad.recorded.should == :seek
+    gz.pos.should == 0
+    gz.read.should == "12345abcde"
+  end
+end